Hi

I have restored a couple of bikes from scratch. The easiest way to get of the old paint and rust (if you don't have acces to sandblasting) is with a crimped wire brush (NOT the cup type) mounted on a drill. I did it on steel and aluminum alloy and it worked perfectly. Don't leave any traces of the old paint because it will show. Then if you can't take it for a professional paint job, you can do it yourself with car spray paint, but this way you will always have to be carefull not to scratch it.
As for the chromed parts, I don't know, I use a polishing machine with a textile covered disk (sorry I don't know what you call it in English) and with a little patience it cleans the surface and leaves it shiny.

Well, if you find this usefull I can give you some more details.